<?php

namespace utils;

class Signature
{
    const TOKEN = 'JIAYI';
    /**
     * @param $str 随机字符串
     * @return string 返回签名
     */
    public static function arithmetic($str = 'FSADFS'){
        $str = $str.self::TOKEN;
        $signature = base64_encode(md5($str));
        return $signature;
    }
}